Inlet choke vane for transverse blower

ABSTRACT

A transverse fan for use in the cleaning and separating system of a combine harvester and wherein such transverse fan is provided with a choke vane mechanism positioned in the air inlet of the aforesaid fan and with such choke vane mechanism adjustable for varying the quantity of air being supplied to a separator and the cleaner without varying the ratio of air being supplied to such separator and such cleaner.

United States Patent 1191 Temple et al.

[111 3,813,184 1451 May 28, 1974 INLET CHOKE VANE FOR TRANSVERSE BLOWER Inventors: William F. Temple, Independence;

David K. Johnston, Blue Springs, both of Mo.

Allis-Chalmers Corporation, Milwaukee, Wis.

Filed: Dec. 1, 1972 Appl. No.: 311,340

Assignee:

US. Cl 415/54, 415/144, 415/147, 137/27 HF Int. Cl. F04d 5/00, F04d 27/00 Field of Search 415/54, 144, 148, 145, 415/147; 137/27 HF; 209/22, 29

References Cited UNITED STATES PATENTS 6/1916 Newcome ..4l5/l48 8/1933 Anderson ..415/54 EPARATOR DucT 3,232,522 2/1966 Laing 415/148 3,460,647 8/1969 Laing 415/54 3,664,349 5/1972 Quick 130/27 HF FORElGN PATENTS OR APPLlCATlONS 291,007 8/1928 Great Britain 415/54 876,620 9/1961 Great Britain 980,684 1/1965 Great Britain 415/54 Primary Examinerl-lenry F. Raduazo Attorney, Agent, or Firm-Kenneth C. McKivett [5 7 ABSTRACT A transverse fan for use in the cleaning and separating system of a combine harvester and wherein such transverse fan is provided with a choke vane mechanism positioned in the air inlet of the aforesaid fan and with such choke vane mechanism adjustable for varying the quantity of air being supplied to a separator and the cleaner without varying the ratio of air being supplied to such separator and such cleaner.

8 Claims, 5 Drawing Figures PATENTEDmzs 1914 B 813 184 saw 1 ar- 3 m min m 2 s :914

SHEH 2 0f 3 SEPARATOR DUCT SEPARATOR DUCT CLEANER DUCT CLEANER DUCT t l g INLET CHOKE VANE FOR TRANSVERSE BLOWER This invention is concerned with providing a combine harvester transverse fan with control mechanism for varying the quantity of air discharged from such fan without varying the fans speed.

This mechanism, when used with a multiple ducted discharge fan configuration, facilitates maintenance of desired air flow ratios between ducts from maximum to minimum. a

In the prior art, previous methods for controlling output from a transverse fan included varying fan speed, obstructing the inlet, obstructing the discharge, and shifting the vortex. These previous methods all have their disadvantages as follows:

a. Varying fan speed complicated drives and increased costs associated with fan configuration;

b. Choking the inlet, discharge duct or ducts can affect the discharge air distribution and in the case of multiple ducted discharge fans, this can adversely change the discharge ratio between ducts, as degree of choking changes; I

c. Devices for changing vortex position and intensity are complex and expensive and they affect air discharge distribution through displacement of the vortex and in multiple duct systems the discharge ratio may be upset.

Present invention permits running a transverse fan wheel at constant speed while controlling the volume of discharged air. The problem inherent in this approach is that while any method of reducing theinlet size will choke the fan, it also tends to randomlychange the ratio of air discharged into one duct to air discharged into the other duct in the multiple ducts system, unless the choking is performed in a certain manner. For most purposes it is desirable that this output ratio remain nearly constant as the fan is choked.

Other features and advantages will appear in the following description and appended claims, reference being had to the accompanying drawings forming a pa of this specification, wherein:

FIG. I is a side elevation of a combine harvester embodying the invention with parts of the combine broken away or removed for clarity of illustration;

FIG. 2 is in enlarged portion of the cleaning and separating fan shown in FIG. 1;

FIG. 3 is a view similar to FIG. 2 showing an alternate construction;

FIG. 4 is a view similar to FIG. 2 showing yet another alternate construction;

FIG. 5 is a graph showing test results for the embodiments shown in FIGS. 1 and 2.

Referring now to the drawings thereis shown in FIG. 1 a side view of a combine designated 10. A cleaning and separating fan ll extends transversely across the lower portion of the combine which includes a frame 12 supported at the rear on dirigible wheels 13. and supported at the front on drive wheels 14. Combine 10 is provided with a header l5, transversely spaced apart sidewalls 16, 16a, and operator stations 17, a grain bin l 8, an engine 19 and a separating and cleaning mechanism 20. A conveyor 21 carries grain and straw from a threshing cylinder (not shown) and discharges same on straw rack 22. Grain cleaning pans 23 are positioned beneath rack 22 and deposit cleaned grain in auger 24 which conveys same to grain bin 18 by means (not shown).

Cleaning and separating fan 11 includes an enclosing casing 26 having end sections 27 which are attached to sidewalls l6 and 16a. A bearing 28 is supported in each ofthe end sections 27 and define a transverse fan axis 29. Fan 11 is provided with a separating duct 31 extending upwardly and rearwardly under conveyor 21 for passing astream of air through material being delivered to straw rack 22 by conveyor 21. Cleaning duct 32 extends rearwardly and upwardly to direct the flow of air under cleaning pans 23.

Referring now to FIG. 2 wherein an enlarged view of the cleaning and separating system 20 is presented removed from the combine 10, this preferred embodiment of the invention includes the casing 26 having transverse sections that extend from sidewall 16 to sidewall 16a therewith to thus form the enclosed casing. One of these transverse sections is the upper surface 33 of separator duct 31 and another of these transverse sections is the lower surface 34- of cleaner duct 32. The fan casing 26 also includes an air intake opening 35 positioned between the upper section 33 of duct 31 and the lower section 34 of duct 32.

A drum shaped rotary fan or blower wheel 36 is supported by bearings 28 for rotationwithin casing 26. The blower wheel 36 includes a central shaft 37 mounted for rotation about axis 29 and a plurality of radially extending discs 38' secured thereto. Blower wheel 36 extends the entire width of casing 26 and a disc 38 is positioned at each end. Mounted on end disc 38 are a series of arcuate blades 39. These blades are mounted in the manner shown in copending application Ser. No. 294,479, filed Dec. 1, 1972 to which reference may be had if further details of the blower wheel 36 are desired.

The blower wheel 36 revolves in counterclockwise direction as seen in FIG. 2 and in so doing draws air through opening 35 and causes it to be discharged between upper section 33 and lower section 34. A transversely extending inlet choke vane 42 is mounted between sidewalls 16, 16a of combine'l0 and includes a transverse axis 43. Choke vane 42 is coextensive with blower wheel 36 and is used to vary the amount of air entering wheel 36.

Wheel 36 is driven by engine 19 at substantially constant speed through conventional drive means not shown. Choke vane 42 is provided with external control members (not shown) for adjusting the position of vane 42 relative to wheel 36. In FIG. 2 the two extreme positions of vane 42 are shown. The full line position is with vane 42 in wide open position and the dotted line position is with vane 42 partially closing air intake opening 35. It is to be noted that the vane 42 divides the air intake opening 35 into a minor air intake passage 44 and a major air intake passage which constitutes the remainder of the opening 35. The minor air intake passage 44, which is defined by the vane 42 and a main cutoff 46 formed by the lower edge of section 33. is a fixed opening extending the full width of the blower wheel 36 which remains constant in effective cross-section for any adjusted position of the choke vane 42. This constant dimension minor air intake passage tends to stabilize the position of the blower vortex 54, thus helping to maintain the same proportionate discharge to the separatorv and cleaner ducts as the position of the choke vane 42 is varied to adjust air intake.

The lower section 47 forms at its lower end, a flow divider 48 for dividing the output air between ducts 31 and 32. Cleaner duct 32 is provided with an upper section 49 whose lower edge is joined with divider 48. Section 49 is also provided with the transverse opening 51 through which chaff, dust or the like can be inspirated and discharged.

Referring to FIG. test results are shown of the embodiment shown in F 16$. 1 and 2. The upper total air curve shows the amount of air being moved for various settings of the choke plate 42. The two lower curves in which the dashed line represents cleaner air and the solid line represents separator air show how closely equal the total air is divided between cleaner and separator.

Referring to FIG. 3 another embodiment of this invention is seen wherein an additional choke plate 42a is installed in opening 35 providing finer adjustment of the air supply. This, of course, required additional mechanism and additional expense. It is to be noted that the passage 44 is preserved.

Referring to H0. 4 another embodiment of the invention is seen using a pair of choke vanes 52 and 53 which are arcuate in cross section and are pivoted at main cutoff 46 and secondary cutoff 50 respectively. This construction is also more expensive than that shown in FIGS. 1 and 2, but by manipulating these plates 52 and 53 the ratio of air in ducts 31 and 32 can be varied. This, of course, is accomplished partially by shifting in the position of vortex 54 which is not done in the preferred embodiment.

The embodiment of the invention in which an exclusive property or privilege is claimed are defined as follows:

l. A combine having a transverse fan for producing a wide and uniform air stream for use in the combine separating system. means for driving such fan at a constant speed, a casing enclosing said fan and including an air intake opening and an air outlet duct, said casing providing a main cut off for air moved by said transverse fan, and transversely extending choke means carried by said combine and being coextensive with said fan, said choke means being positioned adjacent to the periphery of said fan within said air intake opening so as to divide said air intake opening into a minor air in- 2. A combine having a transverse fan as recited in claim 1 and wherein said choke means comprises a choke vane carried by said combine and being coextensive with said fan, said choke vane being mounted for pivotal movement about a transverse axis for movement towards or away from said fan for varying the volume of air entering such fan.

3. A combine having a transverse fan as recited in claim 2 and wherein said outlet duct comprises a separator duct and a cleaner duct, a lower edge of the upper surface of said separator duct forming said main cut off and the lower edge of the lower surface of said separator duct forming a divider for proportioning the air flow to said duct.

4. A combine harvester having a transverse fan as recited in claim 3 and wherein a vortex position is maintained within said fan for any adjusted position of said choke vane.

5. A combine having a transverse fan as recited in claim 3 and wherein the lower transversely extending edge of said cleaner duct forms a secondary cut off at said opening.

6. A combine harvester having a transverse fan as recited in claim 4 and wherein said edges are coextensive with said fan and extend transversely adjacent to the periphery of said fan.

7. A combine having a transverse fan as recited in claim 1 and wherein said air inlet passages extend transversely coextensive with said fan.

8. A combine having a transverse fan as recited in claim 1 and wherein said choke means comprises a plurality of choke means carried by said combine and being coextensive with said fan, said choke means being mounted for pivotal movement about spaced apart transverse axes for movement toward or away from said fan for varying the volume of air entering such fan. 

1. A combine having a transverse fan for producing a wide and uniform air stream for use in the combine separating system, means for driving such fan at a constant speed, a casing enclosing said fan and including an air intake opening and an air outlet duct, said casing providing a main cut off for air moved by said transverse fan, and transversely extending choke means carried by said combine and being coextensive with said fan, said choke means being positioned adjacent to the periphery of said fan within said air intake opening so as to divide said air intake opening into a minor air intake passage between said choke means and said main cut off and a major air intake passage, said choke means being adjustable to a position blocking part of said major air intake passage and positionable to free said major air intake passage and said minor air intake passage remaining constant in effective cross section in all adjusted positions of said choke means.
 2. A combine having a transverse fan as recited in claim 1 and wherein said choke means comprises a choke vane carried by said combine and being coextensive with said fan, said choke vane being mounted for pivotal movement about a transverse axis for movement towards or away from said fan for varying the volume of air entering such fan.
 3. A combine having a transverse fan as recited in claim 2 and wherein said outlet duct comprises a separator duct and a cleaner duct, a lower edge of the upper surface of said separator duct forming said main cut off and the lower edge of the lower surface of said separator duct forming a divider for proportioning the air flow to said duct.
 4. A combine harvester having a transverse fan as recited in claim 3 and wherein a vortex position is maintained within said fan for any adjusted position of said choke vane.
 5. A combine having a transverse fan as recited in claim 3 and wherein the lower transversely extending edge of said cleaner duct forms a secondary cut off at said opening.
 6. A combine harvester having a transverse fan as recited in claim 4 and wherein said edges are coextensive with said fan and extend transversely adjacent to the periphery of said fan.
 7. A combine having a transverse fan as recited in claim 1 and wherein said air inlet passages extend transversely coextensive with said fan.
 8. A combine having a transverse fan as recited in claim 1 and wherein said choke means comprises a plurality of choke means carried by said combine and being coextensive with said fan, said choke means being mounted for pivotal movement about spaced apart transverse axes for movement toward or away from said fan for varyIng the volume of air entering such fan. 